No pesticide residues were detected on about 61% of fresh produce samples collected in 2011 by California officials.

Of the 2,707 retail and wholesale samples tested by the California Department of Pesticide Regulation, about 36% had residues within federally allowed limits. Roughly 3%, mostly imports, had levels that were illegal but did not pose an immediate health risk, according to the agency.

The results included 988 samples of California produce, of which 97.9% were in compliance, according to a news release.

A new technology, liquid chromatography mass spectrometry, was used to analyze about 25% of the results. The state plans a full implementation of the method, which adds to the number of detectable pesticides, including those recently registered.

Products with over-the-limit concentrations of pesticide residues were removed from the market.

In May, the California pesticide agency fined two pesticide dealers — Reedley-based Gar Tootelian Inc. and Traver-based Britz-Simplot Grower Solutions LLC — a combined $105,000 for selling Comite to control peach mites, an unapproved use. That stemmed from a July 2010 finding using the new technology. No health risk was found but about 2.4 million pounds of peaches, worth more than $1.1 million, were taken off the market.

In 2011 the testing method was used on apples, celery, kale, Chinese long beans, potatoes, strawberries, peaches and spinach. Eventually it’s expected to be used on every commodity.

It detected residues on 350 of 449 samples; older screening systems did not pick those up. That difference was expected, as prior methods targeted pesticides like organophosphates that are fading from use. Still, the residues were within allowed limits.

“In addition to most frequently consumed fruits and vegetables like apples and lettuce, we sample tomatillos and other produce used in ethnic cooking,” Brian Leahy, California Department of Pesticide Regulation director, said in the release.

In 2010 and 2011, the state detected illegal residues most often on snow peas from Guatemala; tomatillos, chili peppers, limes and papayas from Mexico; ginger from China; and spinach and kale from California.

The spectrometry was first used in 2009 in a pilot project at the California Department of Food and Agriculture’s Center for Analytical Chemistry in Sacramento. This past fiscal year, DPR increased funding for it to the California Department of Food and Agriculture. The cost is covered by fees on pesticide sales, registrations and licenses.

The residue monitoring data are online.